Colored cellulose esters and ethers



Patented July 10, 1951 COLORED CELLULOS E ESTERS AND ETHERS HenryCharles Olpin, Kenneth Ronald House,

and John Wright, Spondon, near Derby, England, assignors to CelaneseCorporation of America, a corporation of Delaware No Drawing.Application July 10, 1946, Serial No. 682,588. In Great Britain July 20,1945 8 Claims. 1 This invention relates to the production of new dyesand the production of coloured fibres, foils, films and the like ofcellulose acetate or other cellulose esters or ethers or of otherfibreforming or film-forming materials which are,

soluble in organic liquids.

U. S. Patent 2,420,008 and U. S. Patent No. 2,393,652 describe thespinning of coloured fibres from solutions of fibre-forming materials,the said solutions being coloured with a dye having there-;

in a monovalent aliphatic radiele free from sulphonic and carboxylicgroups, the said aliphatic radicle containing at least 8 carbon atomsunited by carbon to carbon linkages, and particularly a monovalentaliphatic hydrocarbon radicle con-..

latter feature seems to be due to the fact that the dye is largely orWholly in solution in the spinning solution and not merely suspendedtherein as in the case of a pigment. Solubility of the dye in thespinning solution is also of great advantage from the point of view ofpreparing homogeneous spinning solutions containing a definite andpredetermined proportion of dye. Moreover when the dye is in solutionthe spinning solution is not likely to lose dye, as does a solutioncontaining apigment, on passage through the filters which must usuallyprecede v the spinning nozzles.

We have now found that coloured fibres,'foils, films and the like offibreor film-forming materials soluble in organic liquids are very advanv tageously prepared with the aid of dyes having two or more aliphaticradicles containing a considerable number of carbon atoms for example 4but preferably at least 6, 8 or more, united by carbon to carbonlinkages. Dyes of thisseries possess high solubility in organic.liquids, notably in acetone, so greatly facilitating the preparation ofcoloured spinning solutions, e. g. of cellulose acetate. Further, fibreswhich are of exceptionally clear shade (and free from greasy appearance)can be obtained. Moreover coloured fibres possessing the excellentfastness to washing and like hot aqueous treatments of fibres colouredwith the dyes specifically described in the above- 2 mentioned U. S.Patent No. 2,420,008 and U. S. Patent No. 2,393,652 can be produced.

The two aliphatic radicles are preferably attached directly to the sameatom, for example a nitrogen atom or a carbon atom, though they may beattached directly to difierent atoms themselves attached to or formingpart of the aryl dye nucleus. The aliphatic radicles may be attached tothe same or different benzene rings of the aryl dye nucleus in the sameor different ways and in any of the ways specified in U. S. Patent2,420,008, and -U; S. Patent No. 2,393,652 for the attachment of thealiphatic radicle containing at least 8 carbon atoms. The followingformulae indicate some of the ways in Which the two aliphatic radiclesR1 and R2 may be attached to an aryl dye nucleus X.

Various saturated and unsaturated aliphatic radicles, preferablyhydrocarbon radicles, may be present. Advantageously the suin of thecarbon atoms in the two aliphatic radicles is at least 10 or 12 andpreferably at least one of the radicles contains at least 8 carbonatoms. The radicles can be either primary, secondary, or tertiary, thatis the carbon atom of the radicle at which attachment to the aryl dyenucleus is effected may be attached directly to 1, 2 or 3 other carbonatoms of the aliphatic radicle. Further the chains of carbon atoms inthe aliphatic radicles may be straight or branched. Advantageously atleast one of the aliphatic radicles contains a chain of at least 6carbon atoms and preferably at least 8 carbon atoms.

Specific examples of aliphtaic radicles which may be present are:

n-Butyl, isobutyl, secondary butyl, n-amyl, isoamyl (CH3)2.CH.CH2.CH2-=,*n-heiiyl, n-octyl, 2-ethyl-n-hexyl, n-undecyl, n dodecyl, secondarydodecyl, n-pentadecyl-, n-hexadecyl, n-heptadecyl-, heptadecyl(9)-(din-octyl-methyl) noctadecyl, decylenyl CH2=CH.(CH2)8-, undecylnylCH2=CI-I.(CH2)9-, heptadecylenyl CH3(CH2) 7.CI-I=CH.(CH2) v,

octadecylenyl CH3.(C1-Iz) 7.CH=CH(CH2) 3-, 8 9- dibrom-heptadecyL, 9 1IO-dibrom-octadeoyl.

It is preferred that one of the aliphatic radicles should contain atleast 4 carbon atoms and the otherat least 6 or 8 carbon atoms. Furtherit is desirable that the aliphatic radicles should be 1 free fromsulphonic and carboxylic groups.

If desired the two aliphatic radicles can be attached directly to thesame carbon atom and the latter attached to the dye nucleus. In thiscase the two aliphatic radicles and the carbon f atom to which they areattached may together be (Cal-I17) 2CH.CO.NH-

The following are examples of radicles comprising the two aliphaticradicles attached to the same carbon atom:

Di (n-o ctyl) -methyl n-Dodecyl-n-butyl-methyl One combination of thealiphatic radicles which has been found to give very good resultsconsists of the two aliphatic radicles, preferably each containing atleast 6 carbon atoms and advantageously at least 8 carbon atoms, forexample 2 octyl radicles (e. g. n-octyl radicles) or two decyl ordodecyl radicles united directly to a nitrogen atom, for example anitrogen atom of a sulphonamide group or of a carboxylic amide group.The presence of such a combination of aliphatic radicles leads to dyesof exceptionally high solubility in acetone, e. g. 5% or more, and withthe aid of dyes containing such a combination of aliphatic radicles,coloured fibres can be produced which withstand very severe hot soapingtreatments without material loss of the dye. A specific example of sucha dye is l-aminoi-p-anisidinoanthraquinone-Z-carboxylic aciddi-octyl-amide.

The dyes can be of various types, for example they can be azo dyescontaining one, two or more azo groups, anthraquinone dyes, or dyes ofthe nitro-diarylamine series. The following are examples of dyes whichcan be made and used in accordance with the invention:

(1) 4-diethylamino-azobenzene 4' carboxylic acid di-octyl-amide (goldenorange) (2) 4 (alpha alpha-di-n-octyl-acetylamino) -4'-dimethylamino-azo-benzene (yellow) (3) -stearoylamino-Z -hydr0xy-5'-dodecylazobenzene (yellow) (4) 4 (alpha: alpha-di-n-octyl-acetylamino)-2- hydroxy-5 -phenyl-azo -benzene yellow) (5) 2:6-dichlor 4 nitro 4'diethylamino-2- (alphazalpha di n octyl-acetylamino) -azobenzene(rubine) (6) 4-nitro-4' -diethy1amino-2 (alpha:alpha-din-octyl-acetylamino) -azo-benzene (red) (7) 4.-nitro-4-diethylamino-2'-(alpha-n-butylalpha n dodecyl acetylamino)-azo-benzene (red) (8) 4 (benzeneazo) -4-diethylamino-2'-(alpha:

' alpha di n-octyl-acetylamino) -azo-benzene (red) (9) 4 (benzeneazo)-4-diethy1amino-2-(alphan biityl alpha-n-dodecyl-acetylamino) -azobenzene (red) (10) Azo dye from diazotised p-nitraniline and 23-hydroxynaphthoic acid anilide-3 -sulphodioctyl amide (red) (11)I-amino 4 p-anisidino-anthraquinone-2- carboxylic di-octyl-amide (blue)(12) l-amino 4 o-anisidino-anthraquinone-2- carboxylic di-octyl-amide(blue) (13) l-amino-4-p-toluido-anthraquinone-2-carboxylic di-octylamide (blue) (14.) 1phenylamino-anthraquinone-2-carboxylicdi-octyl-amide (bluish red) (15) 1 cyclohexylaminoanthraquinone-2-carboxylic di-octyl-amide (bright bluish red) (16)1-methylamino-anthraquinone-2-carboxylic di-octyl-amide (bright bluishred) (17) 2-nitro-diphenylamine-4-carboxylic acid dioctyl-amide (clearyellow) (18) 2 nitro-4'-methoxy-diphenylamine-4-carboxylic aciddi-octyl-amide (golden yellow) (19) 2:4-dinitro-diphenylamine 4carboxylic acid di-octyl-amide (lemon yellow) (20) 2:4 dinitro a(alphatalpha-di-n-octylacetylamino) -diphenylamine (yellow) (2 1) 4-cyclohexylamino -2 -nitro -benzene-4-carboxylic acid di-(n-octyl)-amide yellow) (22) 2 nitro diphenylamine 4 sulpho-di(noctyl) amide(pure yellow) (23) 2 nitro-4-methoxy-diphenylamine-4-sulpho-di(n-0ctyl)-amide (golden yellow) (greenish adequate to enable them to be used forcolouring spinning solutions of cellulose acetate in acetone in suchdepth that the said solutions yield fibres of full shades when spun. Inmany cases it is possible to obtain acetone solutions of strength.

The dyes can be made in various ways. One method is to introduce therequisite aliphatic radicles into dyes containing amino groups, hy-

droxy groups or mercapto groups by-the action of appropriate alkylatingor acidylating agents. Further, dyes containing carboxylic 0r sulphonicgroups can be esterified with alcohols containing the requiste aliphaticradicles. Again a dye containing a reactive halogen atom can besubjected to the action of a secondary amine wherein the radiclesattached to the nitrogen atom are aliphatic radicles of the requiredkind. In par-- ticular a dye containing a carboxylic chloride orsulphonic acid. chloride group may be allowed to react with a secondaryamine of the kind indicated; for example the acid chloride of an azo dyecontaining a sulphonic or carboxylic group, or the acid chloride of a1-amino-4-arylaminoanthraquinone-2-carboxylic acid or the acid chlorideof a nitro-diarylamine carboxylic acid may so be allowed to react. Thedyes numbered 1, 1'7, 18 19, and 21 are most conveniently made by thismethod which can also be used in the case of the dyes numbered 11, 12,and 13. In place of the acid chloride the acid bromide or a methyl,ethyl or other ester of the acid or even the acid itself can be used.

An alternative method is to make the dyes from appropriate componentscontaining the requisite aliphatic radicles. For example, azo dyes canbe obtained by coupling various coupling components (e. g. phenols,amines or pyrazolones) with diazo compounds of amines (includingdiazotized amino-azo-compounds), the coupling components and/or thediazotizable amines containing the requiste aliphatic radicles, forexample in the form of a group -CO.NR1R2 of SO2.NR1R2 wherein R1 and R2are the requisite aliphatic radicles. For instance azo dyes can be madeby coupling a diazo compound with an N-dialkyl-aniline capable ofcoupling in paraposition to the amino group and having adioctoyl-actyl-amino group as a substituent in meta position to thedialkyl amino group. The dyes numbered 5, 6, '7, 8, 9 and 10 in theabove list are conveniently made in this manner.

Likewise, nitro-diarylamine dyes can be obtained by interaction of ahalogen aryl compound and an amino-aryl compound at least one of whichcontains a nitro group and one or both of which carry the requisitealiphatic radicles, for example which carry the requisite aliphaticradicles attached to the nitrogen atom of a carboxylic amide orsulphonamide group.

Thus a nitro-halogen benzene carboxylic or sulphonic amide (particularlya 4-halogen-2- nitrobenzene carboxylic or sulphonic amide) of which theamide nitrogen carries the requisite substituents can be condensed withaniline or with a nuclear alkyl, alkoxy, halogen, amino, or acidylaminosubstitution product thereof, for example p-toluidine, p-octylaniline,p-anisidine, p-phenetidine, p-chloraniline, p-phenylene diamine,p-amino-acetanilide, p-(Z-ethylhexoylamino)-aniline, ormono-benzoyl-p-phenylene diamine. The dyes numbered 22 and 23 in theabove list are very conveniently made in, this way and can also be usedto produce the dyes numbered 17 and 18.

Anthraquinone dyes can be produced by subjecting a halogen anthraquinonecontaining a carboxylic amide or sulphonamide group of which the amidenitrogen carries the requisite aliphatic radicles to the action ofammonia or an alkyl, aryl, or aralkylamine so as to replace a halogenatom by an amino, alkylamino, cyclo-alkylaminoor arylamino group. Thus a1-halogen-anthraquinone-2-carboxylic amide, or a 1 amino 4halogen-anthraquinone-2-carboxylic amide, having the requisite aliphaticradicles attached to the amide nitrogen, may be caused to react with theammonia or amine. The dyes numbered 11 to 16 in the above table are veryconveniently made by this method.

The invention includes the dyes and their methods of manufacture.

The proportions in which the dyes are employed in the production ofcoloured fibres, foils, films, or the like can be within wide limits,for example from 0.5 to 2.5 percent based on the weight of the celluloseacetate or other fibreor film-forming material. Owing to the very highsolubility in acetone cellulose acetate or other fibres or productscontaining very high proportions of the dyes can be produced via acetonesolutions of the cellulose acetate or other materials, in which thewhole of the requisite dye is in solution rather than in suspension.

Either wet or dry methods may be used for spinning into fibres thesolutions of the fibreforming materials containing the dyes; thus fibresmay be produced by spinning the solutions either into suitableevaporative atmospheres or into suitable coagulating baths. Theinvention is of special value in connection with the production ofcoloured cellulose acetate fibres by the spinning of acetone solutionsof cellulose acetate.

The fibres may of course be assembled into yarns at the time of spinningas is commonly practised. Again the fibres may be out up into staplefibre and this, either alone or mixed with other textile fibres e. g.wool, silk, cotton or regenerated cellulose fibres, converted into yarnby the methods commonly employed for converting cotton or wool intoyarns. Yarns consisting of or containing the coloured fibres of theinvention can be formed into fabrics by weaving or knitting. Thecoloured materials produced in accordance with the invention maysubsequently be topped with other dyes and particularly with directdyeing dyes for cellulose esters or ethers, for example thewater-insoluble dyestuffs of the nitrodiarylamine, azo, oramino-anthraquinone series, such as are extensively employed for thecolouration of cellulose acetate materials. The topping colouring mattermay be applied either uniformly or locally according to the eiTects itis desired to produce. The topping colours may be applied, for instance,in aqueous solution or dispersion according to their nature, or insolution in organic solvents. A single coloured material produced inaccordance with the invention can thus be utilised to yield a range ofmaterials of different shades.

The dyes of the present invention, like those of U. S. Patent 2,420,008,and U. S. Patent No. 2,393,652 have as a class little or no affinity forfibres of cellulose esters or ethers or other fibreforming materialswhen applied thereto in the ordinary way as aqueous dispersions. It hasbeen be obtained: by' applying the. dyes. in: the form of.- The organic:

solutions in organic liquid media. liquid media can: be. those referredto in U'. S. Patent No; 23843001 inconnection. with the employment ofarylamino-anthraquinones for colouring cellulose ester or ethermaterials. Again the dye liquids can beapplied to the; ma terials in anyof the ways described in the said. patent.

The invention is of especial value in the production of colouredcellulose acetate fibres,.foils; films and the like. Similar colouredproducts. of other fibre-forming materials soluble. in organic liquids,particularly other cellulose esters or ethers, can be obtained likewise,for example of cellulose propionate, butyrate, aceto-propionat'e,aceto-butyrate, nitroacetate, and of methyl, ethyl and benzylcelluloses, and fibres and other products of polymerised vinylcompounds.

The invention is illustrated by the following examples the partsreferred to being parts by weight.

Example 1 20 parts of 1-amino-i-brom-anthraquinone Z-carboxylic chlorideis boiled for 8 hours: with 200 parts of benzene, parts ofpotassium-acetate, and 14.5 parts of dioctylamine. The benzene isdistilled off and the residue stirred at 130 C. for 3 hours with 125parts of para-anisidine, 15.6 parts ofpotassium acetate, and 3. parts ofcopper acetate. The l-amino--p-anisidinoanthraquinone-Z-carboxylic aciddi-octyl amide is isolated by pouring into a mixture of 210 parts ofconcentratedhydrochloric acid and 250 parts of ice and boiling the oilyprecipitate first with a mixture of 60 parts of concentratedhydrochloric acid and 1000 parts of Water and then with a solution of 10parts of sodium carbonate in 1000 parts of water; the product isfinally-washed with water; Itis very soluble in acetone. By substitutingo-anisidine or aniline for-the p-anisidine tl1e2corresponding'o-anisidinoand anilido-derivatives can be obtained;

By dry-spinning an acetone solution of cellulose acetate (25 percentstrength) containing 1.5% of anyof the dyes based on the weight of thecellulose acetate, blue fibres of very good fastness tosoap scouring areobtained. A mixture of about equal; parts of the p-anisidino ando-anisidino compounds can be employed With'advantage, such a mixturehaving a remarkably high solubility in acetone.

1-phenylamino-anthraquinone 2 carboxylic aciddi-octyl amide and thecorresponding l-cyclohexyla-mino compound can similarly be obtained fromI-chlor-anthraquinone-2- carboxylic chloride, di-octylamine and anilineand cyclohexylamine respectively.

The 1-amino-4-p-anisidino anthraquinone- 2-carboxylic di-octylamideandthe corresponding'o-anisidino and anilido compounds can likewise beobtained'though less advantageously by the action of di-octylamine on1-amino-4-panisidino anthraquinone-Z-carboxylic chloride or thecorresponding o-anisidino or anilido-derivative asrthe case may be.

In this example the di-n-octylaminecan be replaced by an equivalentamount of di-dodecylamine or of di-(2-ethylhexyl) -amine.

Example 2 6.1 parts ofi1-chloranthraquinone-2-carboxylic chloride isboiled for 2 hours with 50 parts: of benzene and 4;82"partsofdi-octylamine. After distilling off the benzene, the residue is boiledunder reflux with 60 parts of methylated spirit, 20 parts of aqueousmethylamine solution (20%. strength), 5 parts of'potassium acetate and0.1 part of copper acetate. The product is cooled, diluted with 400parts water and the precipitated oil washed first with a little 10%sodiumcarbonate solution and then with water. The. oily1-methylamino-anthraquinone-2-carboxylic aciddi-octylamide can then bedissolved in acetone and thesolution incorporated in a cellulose acetatespinning solution from which bluish-red fibres can be spun.

Example '3 27.4 parts of finely ground Z-nitro-i-carboxy-4'-methoxy-di-phenylamine aremixed with 100. parts of toluene and 13parts of thionyl chloride and the mixture-boiled under reflux until thenitro carboxy methoxy di phenylamine has passed into solution and nofurther acid fumes are evolved (usually about 1 hour) 24.1 partsofdi-octylamine are then added and. the mixture refluxed for a furtherhour. After filtering, the tolueneis removed from the filtrate bydistillation whereupon the 2-nitro-di-phenylaminee4- carboxylic aciddi-octylamide remains as a thick oil which is extremely soluble inacetone.

2 :4-dinitro-diphenylamine -4' -carboxylic acid, and2-nitro-di-phenylamine-2'-carboxylic acid can be converted into theirdi-octylamides in a similar manner; The di-octylamides are all verysoluble-in acetone.

Example 4 parts. of 2-nitro-di-phenylamine-4-carboxylic acid is refluxedfor 8 hours with 1000 parts of benzene and 58 partsof thionyl chloride;About three-quarters of the benzene is distilled off. through. afractionating column at ordinary pressure. and the remainingbenzenedistilled ofi under reduced pressure at a temperature below 100 C. Theremaining carboxylic chloride is taken up in 500 parts of benzene, 100parts of din-octylamine and 60 parts of potassium acetate added,.and themixture refluxed for 8 to 1.0 hours; The. mixture is filtered andbenzene removed from the filtrate by distillation under reduced pressureat a temperature below 100. C. 2-nitrodi-phenylamine-4-carboxylic aciddi-octylamide remains as an orange oil,.very solublein acetone. By. dryspinning a 25% acetone solution of cellulose acetate. containing 1.5% ofthe dye (based on.the weight of the cellulose acetate) filaments ofaclear yellow shade are obtained. The coloured filaments are of very goodfastness to light andare very resistant to hot soaping treatments,including the very vigorous treatments necessary to remove the gum fromnatural silk.

The di-n-octylamine in this example-can be replaced by an equivalentamount of di-dodecyl amine, di-(Z-ethylhexyD-amine orbutyl-dodecylamine.

The 2e-nitro-di-phenylamine-4-carboxylic acid dioctylamide can also beobtained, though less advantageously, by heating the dioctylamide of3-nitro-4-chlor-benzoic acid with about6 times its weight of aniline atfor 10 hours and isolating the product by cooling; to 70 C. andpouringinto a mixture of 2 parts of concentrated hydro.- chloric acid and 3parts of crushed ice. The product is then freed from traces of anilineby boiling with dilute hydrochloric acid (1 part of concentrated acid to10 of water) and then with 1 percent sodium carbonate solution, finallybe ing washed with water and dried.

Example 29.7 parts of the azo dye4-diethylamino-azobenzene-4'-carboXylic acid (obtainable by couplingdiazotised p-amino-benzoic acid with dieth-- ylaniline in dilutehydrochloric acid) is mixed with 100 to 150 parts of toluene and 13parts of thionyl chloride and the mixture boiled under reflux, whilestirring, until evolution of, hydrochloric acid ceases (usually about anhour). To the red solution is added 24.1 parts of dioctylamine andrefluxing continued for a further hour, the liquid becoming more yellowin colour. The reaction mixture is filtered hot and the toluene removedfrom the filtrate by distillation, at first at ordinary pressure andfinally under reduced pressure at a temperature not exceeding 120 C. Thedye remaining is a dark orange viscous fluid, very soluble in acetone.By dry spinning a 25% acetone solution of cellulose acetate containing1.5% of the dye (based on the cellulose acetate) filaments are obtainedwhich are of a golden orange shade very resistant to hot soapingtreatments.

Example 6 42 parts of 4-chlor-3-nitroben2ene-sulphonic' acid(ii-octylamide (obtainable by the action of dioctylamine on4-chlor-3-nitrobenzene sulphochloride) is boiled for 5 hours with partsof aniline, 6 parts of sodium carbonate (anhydrous) and 250 parts ofwater. The red oil obtained is separated from the aqueous liquid andwashed, first with water, then with dilute hydrochloric acid and finallywith water. It is very soluble in acetone (more than 10%). By dryspinning a 25% acetone solution of cellulose acetate containing 1.5% ofthe dye (based on the weight of the cellulose acetate) filaments areobtained which are of a pure yellow shade very resistant to hot soapingtreatments.

By replacing the aniline with an equivalent amount of p-anisidine thecorresponding 4'-meth oxy-2-nitro-diphenylamine-4-sulphonic aciddioctylamide is obtained. By dry spinning a 25% acetone solution ofcellulose acetate containing 1.5% of the dye filaments are obtainedwhich are of a golden yellow shade very resistant to hot soapingtreatments.

The dioctylamide compounds used in this example can be replaced by thecorresponding didodecylamide compounds or the butyl-dodecylamidecompounds with the production of dyes of very similar properties.

Having described our invention, what we desire to secure by LettersPatent is:

l. Fiber-forming materials, selected from the group consisting ofcellulose ester and cellulose ethers, soluble in organic liquids, saidfiber-formmg materials being colored with a dye which contains twomonovalent aliphatic hydrocarbon radicles each of which contains from 8to 18 carbon atoms united by carbon to carbon linkages, the chromophoricnucleus of said dye being free from sulphonic acid and carboxylic acidgroups and being selected from the group consisting of the anthraquincnenucleus, the azo-benzene nucleus and the nitro-diphenylamine nucleus.

2. Fibers of an organic acid ester of cellulose soluble in organicliquids colored with a dye which contains two monovalent aliphatichydrocarbon radicles each of which contains from 8 to 18 carbon atomsunited by carbon to carbon linkages, the chromophoric nucleus of saiddye being free from sulphonic acid and carboxylic acid groups and beingselected from the group consisting of the anthraquinone nucleus, theambenzene nucleus and the nitro-diphenylamine nucleus.

3. Cellulose acetate fibers colored with a dye which contains twomonovalent aliphatic hydrocarbon radicles each of which contains from 8to 18 carbon atoms united by carbon to carbon linkages, the chromophoricnucleus of said dye being free from sulphonic acid and carboxylic acidgroups and being selected from the group consisting of the anthraquinonenucleus, the azobenzene nucleus and the nitro-diphenylamine nucleus.

4. Colored fibers according to claim 3 wherein the monovalent aliphatichydrocarbon radicles are present in the dye in the form of a group-CO.NR1R2, wherein R1 and R2 are the aliphatic radicles.

5. Cellulose acetate fibers colored with an anthraquinone compoundhaving an amino group in the 1-position, an arylamino group of thebenzene series in the 4-position and in the 2- position a groupCO.NR1R2, wherein R1 and R2 are monovalent aliphatic hydrocarbonradicles each of which contains from 8 to 18 carbon atoms linked bycarbon to carbon linkages.

6. Cellulose acetate fibers colored with 2-nitrodiphenylamine havingdirectly attached to a phenyl nucleus a group CO.NR1R2, wherein R1 andR2 are monovalent aliphatic hydrocarbon radicles each of which containsfrom 8 to 18 carbon atoms linked by carbon to carbon linkages.

7. Cellulose acetate fibers colored with 1-aminc-4-phenylamino-anthraquinone 2 carboxylic acid-dioctylamide.

8. Cellulose acetate fibers colored with2-nitrodiphenylamino-4-carboxylic acid-dioctylamide.

HENRY CHARLES OLPIN. KENNETH RONALD HOUSE. JOHN WRIGHT.

REFERENCES CITED The following references are of record in the file ofthis patent:

UNITED STATES PATENTS Number Name Date 1,074,429 Gunther Sept. 30, 19131,903,600 Schweiter Apr. 11, 1933 2,083,308 Senn June 8, 1937 2,086,591Whitehead July 13, 1937 2,101,323 Salzberg Dec. 7, 1937 2,105,519 BodellJan. 13, 1938 2,111,300 Senn Mar. 15, 1938 2,112,403 Krzikalla et alMar. 29, 1938 2,145,580 Bley Jan. 31, 1939 2,193,151 Zerweck et a1 Mar.12, 1940 2,241,251 Franklin May 6, 1941 2,288,531 Klarer June 30, 19422,294,968 Ellis et al Sept. 8, 1942 2,347,704 McNally et a1 May 2, 19442,388,663 Argyle Nov. 13, 1945 2,393,652 Olpin Jan. 29, 1946 2,420,008Olpin May 6, 1947 2,420,453 Sutter May 13, 1947 FOREIGN PATENTS NumberCountry Date 501,913 Great Britain Mar. 8, 1939

1. FIBER-FORMING MATERIALS, SELECTED FROM THE GROUP CONSISTING OFCELLULOSE ESTER AND CELLULOSE ETHERS, SOLUBLE IN ORGANIC LIQUIDS, SAIDFIBER-FORMING MATERIALS BEING COLORED WITH A DYE WHICH CONTAINS TWOMONOVALENT ALIPHATIC HYDROCARBON RADICALS EACH OF WHICH CONTAINS FROM 8TO 18 CARBON ATOMS UNITED BY CARBON TO CARBON LINKAGES, THE CHROMOPHORICNUCLEUS OF SAID DYE BEING FREE FROM SULPHONIC ACID AND CARBOXYLIC ACIDGROUPS AND BEING SELECTED FROM THE GROUP CONSISTING OF THE ANTHRAQUINONENUCLEUS, THE AZO-BENZENE NUCLEUS AND THE NITRO-DIPHENYLAMINE NUCLEUS.